Proceedings of the 6th ACM Multimedia Systems Conference最新文献_第3页

Transcoding live adaptive video streams at a massive scale in the cloud 在云中大规模地转码实时自适应视频流

Proceedings of the 6th ACM Multimedia Systems Conference Pub Date : 2015-03-18 DOI: 10.1145/2713168.2713177

R. Aparicio-Pardo, Karine Pires, Alberto Blanc, G. Simon

{"title":"Transcoding live adaptive video streams at a massive scale in the cloud","authors":"R. Aparicio-Pardo, Karine Pires, Alberto Blanc, G. Simon","doi":"10.1145/2713168.2713177","DOIUrl":"https://doi.org/10.1145/2713168.2713177","url":null,"abstract":"More and more users are watching online videos produced by non-professional sources (e.g., gamers, teachers of online courses, witnesses of public events) by using an increasingly diverse set of devices to access the videos (e.g., smartphones, tablets, HDTV). Live streaming service providers can combine adaptive streaming technologies and cloud computing to satisfy this demand. In this paper, we study the problem of preparing live video streams for delivery using cloud computing infrastructure, e.g., how many representations to use and the corresponding parameters (resolution and bit-rate). We present an integer linear program (ILP) to maximize the average user quality of experience (QoE) and a heuristic algorithm that can scale to large number of videos and users. We also introduce two new datasets: one characterizing a popular live streaming provider (Twitch) and another characterizing the computing resources needed to transcode a video. They are used to set up realistic test scenarios. We compare the performance of the optimal ILP solution with current industry standards, showing that the latter are sub-optimal. The solution of the ILP also shows the importance of the type of video on the optimal streaming preparation. By taking advantage of this, the proposed heuristic can efficiently satisfy a time varying demand with an almost constant amount of computing resources.","PeriodicalId":202494,"journal":{"name":"Proceedings of the 6th ACM Multimedia Systems Conference","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123023754","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 76

RAISE: a raw images dataset for digital image forensics RAISE:用于数字图像取证的原始图像数据集

Proceedings of the 6th ACM Multimedia Systems Conference Pub Date : 2015-03-18 DOI: 10.1145/2713168.2713194

Duc-Tien Dang-Nguyen, Cecilia Pasquini, V. Conotter, G. Boato

{"title":"RAISE: a raw images dataset for digital image forensics","authors":"Duc-Tien Dang-Nguyen, Cecilia Pasquini, V. Conotter, G. Boato","doi":"10.1145/2713168.2713194","DOIUrl":"https://doi.org/10.1145/2713168.2713194","url":null,"abstract":"Digital forensics is a relatively new research area which aims at authenticating digital media by detecting possible digital forgeries. Indeed, the ever increasing availability of multimedia data on the web, coupled with the great advances reached by computer graphical tools, makes the modification of an image and the creation of visually compelling forgeries an easy task for any user. This in turns creates the need of reliable tools to validate the trustworthiness of the represented information. In such a context, we present here RAISE, a large dataset of 8156 high-resolution raw images, depicting various subjects and scenarios, properly annotated and available together with accompanying metadata. Such a wide collection of untouched and diverse data is intended to become a powerful resource for, but not limited to, forensic researchers by providing a common benchmark for a fair comparison, testing and evaluation of existing and next generation forensic algorithms. In this paper we describe how RAISE has been collected and organized, discuss how digital image forensics and many other multimedia research areas may benefit of this new publicly available benchmark dataset and test a very recent forensic technique for JPEG compression detection.","PeriodicalId":202494,"journal":{"name":"Proceedings of the 6th ACM Multimedia Systems Conference","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124040345","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 408

The toulouse vanishing points dataset 图卢兹消失点数据集

Proceedings of the 6th ACM Multimedia Systems Conference Pub Date : 2015-03-18 DOI: 10.1145/2713168.2713196

Vincent Angladon, Simone Gasparini, V. Charvillat

引用次数: 10

Analysis and characterization of a video-on-demand service workload 视频点播服务工作负载的分析与表征

Proceedings of the 6th ACM Multimedia Systems Conference Pub Date : 2015-03-18 DOI: 10.1145/2713168.2713183

A. Ali-Eldin, M. Kihl, Johan Tordsson, E. Elmroth

{"title":"Analysis and characterization of a video-on-demand service workload","authors":"A. Ali-Eldin, M. Kihl, Johan Tordsson, E. Elmroth","doi":"10.1145/2713168.2713183","DOIUrl":"https://doi.org/10.1145/2713168.2713183","url":null,"abstract":"Video-on-Demand (VoD) and video sharing services account for a large percentage of the total downstream Internet traffic. In order to provide a better understanding of the load on these services, we analyze and model a workload trace from a VoD service provided by a major Swedish TV broadcaster. The trace contains over half a million requests generated by more than 20000 unique users. Among other things, we study the request arrival rate, the inter-arrival time, the spikes in the workload, the video popularity distribution, the streaming bit-rate distribution and the video duration distribution. Our results show that the user and the session arrival rates for the TV4 workload does not follow a Poisson process. The arrival rate distribution is modeled using a lognormal distribution while the inter-arrival time distribution is modeled using a stretched exponential distribution. We observe the \"impatient user\" behavior where users abandon streaming sessions after minutes or even seconds of starting them. Both very popular videos and non-popular videos are particularly affected by impatient users. We investigate if this behavior is an invariant for VoD workloads.","PeriodicalId":202494,"journal":{"name":"Proceedings of the 6th ACM Multimedia Systems Conference","volume":"101 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132512417","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 27

A multi-lens stereoscopic synthetic video dataset 一个多镜头立体合成视频数据集

Proceedings of the 6th ACM Multimedia Systems Conference Pub Date : 2015-03-18 DOI: 10.1145/2713168.2713199

Fan Zhang, W. Feng, Feng Liu

引用次数: 5

Optimizing the video transcoding workflow in content delivery networks 优化内容交付网络中的视频转码工作流程

Proceedings of the 6th ACM Multimedia Systems Conference Pub Date : 2015-03-18 DOI: 10.1145/2713168.2713175

Dilip Kumar Krishnappa, M. Zink, R. Sitaraman

{"title":"Optimizing the video transcoding workflow in content delivery networks","authors":"Dilip Kumar Krishnappa, M. Zink, R. Sitaraman","doi":"10.1145/2713168.2713175","DOIUrl":"https://doi.org/10.1145/2713168.2713175","url":null,"abstract":"The current approach to transcoding in adaptive bit rate streaming is to transcode all videos in all possible bit rates which wastes transcoding resources and storage space, since a large fraction of the transcoded video segments are never watched by users. To reduce transcoding work, we propose several online transcoding policies that transcode video segments in a \"just-in-time\" fashion such that a segment is transcoded only to those bit rates that are actually requested by the user. However, a reduction in the transcoding work should not come at the expense of a significant reduction in the quality of experience of the users. To establish the feasibility of online transcoding, we first show that the bit rate of the next video segment requested by a user can be predicted ahead of time with an accuracy of 99.7% using a Markov prediction model. This allows our online algorithms to complete transcoding the required segment ahead of when it is needed by the user, thus reducing the possibility of freezes in the video playback. To derive our results, we collect and analyze a large amount of request traces from one of the world's largest video CDNs consisting of over 200 thousand unique users watching 5 million videos over a period of three days. The main conclusion of our work is that online transcoding schemes can reduce transcoding resources by over 95% without a major impact on the users' quality of experience.","PeriodicalId":202494,"journal":{"name":"Proceedings of the 6th ACM Multimedia Systems Conference","volume":"54 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131423914","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 45

EMOD

Proceedings of the 6th ACM Multimedia Systems Conference Pub Date : 2015-03-18 DOI: 10.1145/2713168.2713172

Dawei Li, Mooi Choo Chuah

{"title":"EMOD","authors":"Dawei Li, Mooi Choo Chuah","doi":"10.1145/2713168.2713172","DOIUrl":"https://doi.org/10.1145/2713168.2713172","url":null,"abstract":"Recently, researchers have proposed solutions to build on-device mobile visual search (ODMVS) systems. Different from traditional client-server mobile visual search systems, an ODMVS supports image searching directly within a mobile device. An ODMVS needs to be designed with constrained hardware in mind e.g. limited memory, less powerful CPU. In this paper, we present, EMOD, an efficient on-device mobile visual search system based on the Bag-of-Visual-Word (BOVW) framework but uses a small visual dictionary. An Object Word Ranking (OWR) algorithm is proposed to efficiently identify the most useful visual words of an image so as to construct a compact image signature for fast retrieval and greatly improved retrieval performance. Due to having a small visual dictionary, we propose the Top Inverted Index Ranking scheme to reduce the number of candidate images for similarity calculation. In addition, EMOD adopts a more efficient version of the recently proposed Ranking Consistency re-ranking algorithm for further performance enhancement. Via extensive experimental evaluations, we demonstrate that our prototype EMOD system yields good retrieval accuracy and query response times for a database with over 10K images.","PeriodicalId":202494,"journal":{"name":"Proceedings of the 6th ACM Multimedia Systems Conference","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121921306","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 12

Screencast dissected: performance measurements and design considerations 截屏分析:性能测量和设计考虑

Proceedings of the 6th ACM Multimedia Systems Conference Pub Date : 2015-03-18 DOI: 10.1145/2713168.2713176

Chih-Fan Hsu, Tsung-Han Tsai, Chun-Ying Huang, Cheng-Hsin Hsu, Kuan-Ta Chen

{"title":"Screencast dissected: performance measurements and design considerations","authors":"Chih-Fan Hsu, Tsung-Han Tsai, Chun-Ying Huang, Cheng-Hsin Hsu, Kuan-Ta Chen","doi":"10.1145/2713168.2713176","DOIUrl":"https://doi.org/10.1145/2713168.2713176","url":null,"abstract":"Dynamic and adaptive binding between computing devices and displays is increasingly more popular, and screencast technologies enable such binding over wireless networks. In this paper, we design and conduct the first detailed measurement study on the performance of the state-of-the-art screencast technologies. Several commercial and one open-source screencast technologies are considered in our detailed analysis, which leads to several insights: (i) there is no single winning screencast technology, indicating rooms to further enhance the screencast technologies, (ii) hardware video encoders significantly reduce the CPU usage at the expense of slightly higher GPU usage and end-to-end delay, and should be adopted in future screencast technologies, (iii) comprehensive error resilience tools are needed as wireless communication is vulnerable to packet loss, (iv) emerging video codecs designed for screen contents lead to better Quality of Experience (QoE) of screencast, and (v) rate adaptation mechanisms are critical to avoiding degraded QoE due to network dynamics. Furthermore, our measurement methodology and open-source screencast platform allow researchers and developers to quantitatively evaluate other design considerations, which will lead to optimized screencast technologies.","PeriodicalId":202494,"journal":{"name":"Proceedings of the 6th ACM Multimedia Systems Conference","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128567941","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 12

Integrated prefetching and caching for adaptive video streaming over HTTP: an online approach 基于HTTP的自适应视频流集成预取和缓存:一种在线方法

Proceedings of the 6th ACM Multimedia Systems Conference Pub Date : 2015-03-18 DOI: 10.1145/2713168.2713181

Ke Liang, Jia Hao, Roger Zimmermann, David K. Y. Yau

{"title":"Integrated prefetching and caching for adaptive video streaming over HTTP: an online approach","authors":"Ke Liang, Jia Hao, Roger Zimmermann, David K. Y. Yau","doi":"10.1145/2713168.2713181","DOIUrl":"https://doi.org/10.1145/2713168.2713181","url":null,"abstract":"We present an integrated prefetching and caching proxy, termed iPac, for HTTP-based adaptive video streaming services like Netflix and YouTube. The challenge we address is maximizing the byte-hit ratio for proxies through prefetching in the context of the limited bandwidth between proxies and content servers. The problem is NP-hard, and the best approximation ratio that any optimal offline algorithm can achieve is 1-e--1 ≈ 0.63. Considering that offline algorithms cannot be applied to real-time applications with stringent time constraints, we propose a novel 0.5-competitive online prefetching algorithm which, to the best of our knowledge, has the best lower bound so far. We evaluate the performance of iPac by deploying it over the Amazon EC2 cloud accepting user requests from the video clients deployed on the PlanetLab based on a real trace of user requests for YouTube videos. Our experimental results demonstrate that iPac can significantly improve the performance in terms of byte-hit ratio (up to 84%) and video rates (up to 34%), compared with the state-of-the-art approaches. The proposed iPac is compatible with existing HTTP-based adaptive streaming implementations without requiring any modification to existing content servers and video clients.","PeriodicalId":202494,"journal":{"name":"Proceedings of the 6th ACM Multimedia Systems Conference","volume":"116 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127248059","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 28

Dynamic configuration of single frequency networks in mobile streaming systems 移动流媒体系统中单频网络的动态配置

Proceedings of the 6th ACM Multimedia Systems Conference Pub Date : 2015-03-18 DOI: 10.1145/2713168.2713179

Saleh Almowuena, M. Hefeeda

{"title":"Dynamic configuration of single frequency networks in mobile streaming systems","authors":"Saleh Almowuena, M. Hefeeda","doi":"10.1145/2713168.2713179","DOIUrl":"https://doi.org/10.1145/2713168.2713179","url":null,"abstract":"Although the capacity of cellular networks has increased with recent generations, the growth in demand of wireless bandwidth has outpaced this increase in capacity. Not only more users are relying on wireless networks, but also the demand from each user has substantially increased. For example, it has become common for mobile users to stream full TV episodes, sports events, and movies while on the go. Further, as the capabilities of mobile devices improve, the demand for higher quality and even 3D videos will escalate, which will strain cellular networks. Therefore, efficient utilization of the expensive and limited wireless spectrum remains an important problem, especially in the context of multimedia streaming services that consume a large portion of the wireless capacity. In this paper, we introduce the idea of dynamically configuring cells in wireless networks to form single frequency networks based on the multimedia traffic demands from users in each cell. We formulate the resource allocation problem in such complex networks with the goal of maximizing the number of served multimedia streams. We prove that this problem is NP-Complete, and we propose a heuristic algorithm to solve it. Through detailed packet-level simulations, we show that the proposed algorithm can achieve substantial improvements in the number of streams served as well the energy saving of mobile devices. For example, our algorithm can serve up to 40 times more users compared to the common unicast streaming approach, and it achieves at least 80% and up to 400% improvement compared to multicast approaches that do not use single frequency networks.","PeriodicalId":202494,"journal":{"name":"Proceedings of the 6th ACM Multimedia Systems Conference","volume":"246 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121126674","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3